Maybe it won't be Amazon.com Inc. (AMZN)  that disrupts healthcare after all.

Walmart Inc. (WMT) is looking into buying PillPack for under $1 billion, CNBC reported late Monday, citing two sources familiar with the situation. The company is a Cambridge, Mass.-based startup that fills and delivers prescription medicine. The rumors come on the heels of reports that the retailer is also interested in acquiring Humana Inc. (HUM) , the $39 billion health insurance company. 

Walmart has its own pharmacy service, which is the fourth largest pharmacy operator in the U.S., according to Pembroke Consulting. The retailer's discussions with PillPack have gone on for months, according to the sources. No deal is finalized, and Amazon has also expressed interest in the company at one point, sources told CNBC.

Walmart and Amazon are among a handful of giants eager to penetrate the trillion-dollar healthcare market. Amazon announced earlier this year that it would form a technology-driven solution alongside JPMorgan Chase & Co. (JPM) and Berkshire Hathaway Inc. (BRK.A) to provide low-cost services to their employees. Meanwhile, CVS Health Corp. (CVS) is well underway with its $69 billion merger with insurance company Aetna Inc. (AET) .

PillPack, founded in 2013, has raised nearly $118 million in venture capital funding. Its latest round was led by Astral Capital.

The foray into healthcare, however, will not be easy.

"Very successful people have gone into healthcare and failed," Tom Charland, the founder and CEO of Merchant Medicine, told TheStreet late last year, when reports surfaced that Apple Inc. was in talks to acquire health clinic startup Crossover Health.

"We've seen it before with Microsoft and Steve Case of AOL," he said, pointing to Microsoft's unsuccessful bid to digitize the health-records system and Case's failed health social-network startup, Revolution Health.

Neither Walmart nor PillPack responded immediately to a request for comment from TheStreet.

Amazon and JPMorgan Chase are holdings in Jim Cramer's Action Alerts PLUS Charitable Trust Portfolio. Want to be alerted before Cramer buys or sells AMZN and JPM? Learn more now.

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